1. Field of the Invention
The present invention relates to a system for providing guiding information for use in detecting and accessing a mobile object having a desired attribute from among a group of a number of unspecified mobile objects such as human beings, creatures, objects, etc. capable of moving in a space.
2. Description of the Related Art
The conventional systems for measuring and using the location of a mobile object can be roughly dividing into two groups, that is, A) systems which use their own positional information, and B) systems which use others' positional information.
A typical example in the group A is a navigation system. A navigation system mainly aims at supporting a mobile object moving to a desired destination. In most cases, the navigation system includes: a unit for measuring the current position using, for example, a GPS (global positioning system), etc.; road map data stored in a storage medium; a unit for having a matching check between the measured current position and the road map data; a unit for planning (computing) the route to the destination; a unit for guiding a user based on the planned route to the destination; a display; a unit for outputting voice, etc.
Since the navigation system is designed as described above, the current position of each system can be displayed on the screen, a moving route to a desired destination can be computed according to road map data, and a mobile object can be guided using voice, etc. based on the computed moving route. With the above described functions, the navigation system is provided for a car, a ship, an aircraft, etc. Recently, it is also used for a portable electronic appliance.
A typical example in the group B is a position management system. The position management system aims at, for example, allowing a user of a position management center to obtain the location of a mobile object, which is separated from the user, and manage and use the obtained position of the mobile object. In most cases, the position management system includes: a unit for measuring the location of a mobile object separate from the user; a unit for transmitting measured positional information to a position management center; a unit for managing the position of the mobile object according to the transmitted positional information; a unit for using the positional information of the mobile object, etc.
Published examples relating to the technology of the above described group B are described as follows.
(a) Japanese Patent Laid-Open No.4-117823 `APPARATUS AND METHOD FOR MANAGING POSITION OF MOBILE OBJECT BASED ON MOBILE COMMUNICATIONS SYSTEM`
This relates to a mobile object position management system capable of measuring the position of a mobile object on the receiver side, and transmitting the measurement result by radio.
(b) Japanese Patent Laid-Open No.9-247730 `METHOD AND APPARATUS FOR DETECTING POSITION`
This relates to a position detection apparatus for mounting an appliance connected to a GPS receiver and a portable telephone such as a PHS (personal handyphone system), etc. onto an object whose position is to be detected, calling the portable telephone from a searcher, thereby detecting by the GPS receiver the position of the object whose position is to be detected, and transmitting the positional information to the searcher through the portable telephone.
(c) Japanese Patent Laid-Open No.8-511408 `PERSONAL LOCATOR SYSTEM`
This relates to a system and a method for detecting a person or an object carrying a portable locator unit (PLU) in a communications network. The position of the PLU is assumed to be in the area covered by a service node.
(d) Japanese Patent Laid-Open No.9-68427 `APPARATUS, SYSTEM, AND METHOD FOR CONFIRMING POSITION`
This relates to a position confirmation apparatus including a target detection unit, a communications unit, a distance specification unit, and a direction specification unit. Each of a plurality of mobile objects carries the position confirmation apparatus to display the distance and the direction from a mobile object to another mobile object (or to a target point).
The above described position management systems are used to manage the position of a business car such as a taxi, a home-delivery car, etc. in a predetermined area, manage the position of a person such as a salesman, a customer engineer (CE), etc., or detect the position of a stray old person, a child, or an object which easily gets lost.
To lead a person along a route to a desired destination using a conventional navigation system, it is necessary to determine a destination, and fix the position coordinates of the destination. Normally, the position coordinates of a destination can be obtained by searching a destination from the map information database stored in a storage device such as CD-ROM, a DVD, a hard disk, etc. A method for retrieving a desired destination from map information database can be a method for directly searching for a destination while a user is looking at a map displayed on the display screen, a method for retrieving a destination according to the information obtained by having a user input the address, the telephone number, the name, the type, etc. of the destination.
However, according to the conventional navigation system, it is difficult to lead a user along a route to a destination which is the location of a mobile object possibly moving in a space because the conventional navigation system has no unit for detecting a specified mobile object from a group of a number of mobile objects, or, if the specified mobile object can be detected, it has no unit for obtaining the position coordinates of a mobile object. Therefore, the conventional navigation system cannot detect a specified mobile object satisfying a desired condition, and provide guiding information for reaching the mobile object.
In addition, the conventional position management system aims at managing, for example, the position of a customer engineer visiting customers, detecting as soon as possible a stray old person, a child, etc. when they get lost. That is, the conventional position management system is based on that a mobile object to be managed is predetermined. To specify a predetermined mobile object, unique identification information such as an ID, etc. preliminarily set for each mobile object is used. The identification information can be the telephone number of a mobile phone connected to a portable device carried by a mobile object, an ID number assigned to the portable device, etc.
Therefore, the conventional position management system cannot detect a mobile object having an attribute requested by a user from a group of a number of unspecified mobile objects, or provide guiding information about a detected mobile object. Furthermore, since the conventional method preliminarily knows a mobile object to be managed, it is not necessary to have sufficient security to protect the privacy of the mobile object to be managed.